The present invention relates to a method and system for collating a plurality of groups of mail items, each group being pre-sequenced according to prioritized delivery addresses, into a final sequenced set of the mail items from the groups, utilizing the prioritized delivery addresses. More specifically, the present invention relates to a process and system that merges several sequenced bundles of flats mail into one sequenced set of mail for delivery by a mail carrier according to a prioritized delivery address sequence, commonly known as a delivery order sequence (DOS) or walk sequence (WS).
Flats mail, routinely delivered by mail carriers, includes magazines, newspapers, padded envelopes, single sheet fliers, compact disks in boxes, poly-wrapped items, and miscellaneous other types of mail items. These flats range in size from 4xe2x80x3 to 15.75xe2x80x3 in length; 4xe2x80x3 to 12xe2x80x3 in width; 0.007xe2x80x3 to 1.25xe2x80x3 in thickness; and {fraction (1/100)} lb. to 6 lb. in weight. Delivery of these flats in delivery order sequence, or walk sequence, requires special sorting in a post office facility such as a delivery unit (DU). In general, DU operations are consistent from one office to another within the U.S. postal system. However, different route types (rural, city, park and loop) may process flats in slightly different manners within the same facility. The flats to be processed arrive from a variety of sources in a number of different ways. Mailers may drop ship saturation mailings (mass mailings) two to seven days prior to the delivery per an agreement with the local Postmaster. Other mailings can arrive on pallets (periodicals, national advertisements or catalogs) after passing through the postal network of facilities as cross-dock material. Other material may be broken down from pallets at an upstream facility if a pallet was shipped as three-digit material. Other flats may have been processed on flats sorting equipment known in the art, and are then processed according to carrier route. Still more material can pass through bulk mail centers as bundles before arriving at the delivery unit (DU).
Currently, with the exception of saturation (mass) mailings, the majority of this material is not in carrier walk sequence (WS) or delivery order sequence (DOS). Bundles may be in enhanced carrier line-of-travel (ECLOT) or in carrier route, but not walk sequence. Less than 1% of the mailings in the field have an eleven digit (ZIP+4+2) delivery point barcode representative of the delivery point sequence (DPS). Many saturation mailings have no barcode at all and are addressed to xe2x80x9cPostal Customerxe2x80x9d with no address. Other mailings have 5 or 9 digit ZIP codes and xe2x80x9cmarriagexe2x80x9d mailings consisting of two materials; an address card or leaflet, and a second mailing with no address label intended to be left at the same address as the card. However, in order to provide for flats bundle collating in an automated fashion, it is possible to provide all of the flats mail with eleven digit coding inclusive of delivery point sequence information.
In current operations, the source and configuration of the flats being processed has little or no impact on how they are processed in the DU in preparation for delivery. In general, the following preparation of flats for delivery occurs (there are other activities such as held mail or registered mail that are performed that are not noted here to simplify the explanation):
1. In preparation for casing operations, mail personnel sort through flats, bundles and mailings from all sources and separate them by carrier early in the morning (beginning around 4:00 AM). This is done in staging areas using tubs, hampers or large cases.
2. Flats are delivered to the carrier casing area and set in a staging area.
3. Carriers case the flats, along with other mail types (this activity is performed in the morning usually from 6:00 AM or 7:00 AM to sometime between 9:00 AM and 11:00 AM, depending on route size and the amount of mail). The current postal standard for casing unsequenced flats is 8 per minute. On some routes or in some DU""s, carriers do not case saturation mailings and treat them as an additional bundle during delivery. Other carriers may split saturation mailings and deliver portions of them on consecutive days to load level the amount of mail to be delivered.
4. Cased mail is removed and placed in trays to be delivered.
5. The carrier leaves the facility and delivers the mail.
6. In some DU""s, carriers case mail upon return to the facility in the afternoon in preparation for the next day.
For some portion of the morning, activities 1 and 2 above, can overlap with the casing operation and may extend until after the carrier has left the facility leaving mail to be cased either later that day or the next morning. All cased mail is removed in carrier walk sequence, and carriers carefully case flats so that all address labels are on the same edge of the mail (even if this means that the label is upside down relative to other addresses in the bundle) to ensure easy reading while doing deliveries. Depending on the route type and/or the carrier""s preference, marriage mailings may case either the address card or both the address card and the mailing cased (some prefer to case only the card and pull the mailing at each house that has a card in the delivery).
These activities can take up to 50% of a carrier""s in-office time, and therefore, limit the amount of deliveries can perform in the remainder of the day. This is one of the limiting factors in the number of stops that a carrier route can contain (obviously the amount of mail, the distance between the stops, the demographics of the route area, and other factors are involved as well). It stands to reason, that by making the in-office activities more efficient, i.e. providing delivery point sequence (DPS) flats, then carriers can be expected to spend less time in the facility and more time on the route. This added time can allow for additional stops on routes and the possible consolidation of some routes into others. This scenario is analogous to the introduction of DPS letter mail through the use of automation to a great degree. However, the types of mail (flats) and the different ways that the mail arrives at a facility does make the task of creating a single bundle of DPS flats a challenging proposition. The automation of sorting and collating of flats by their physical nature is a very difficult task due to the large variation sizes and types of the flats material.
Accordingly, it is a primary object of the present invention to develop a system and process for collating flats mail using a small, flexible, inexpensive machine that is easy to operate, reliable, and requires easy and infrequent maintenance.
It is the further object of the present invention to develop a process and system which utilizes standard sort schemes for carrier walk sequences utilized for sorting conventional mail other than flats.
It is another object of the present invention to provide an apparatus for sorting flats having a small footprint in order to take up a minimum amount of space in the sorting facility.
It is yet another object of the present invention to provide an apparatus for sorting flats, which is modular in construction for flexible sizing through the use of additional modular components, including staging towers.
It is still another object of the present invention to provide an apparatus for sorting flats wherein only a single operator is required.
It is another object of the present invention to provide an apparatus for sorting flats having low maintenance and operating costs.
The objects of the present invention are fulfilled by providing a method and apparatus for collating a plurality of groups of mail items, such as flats, each group being pre-sequenced according to prioritized delivery addresses (delivery order sequence DOS), into a final sequenced set of the mail items from the groups, utilizing the prioritized delivery addresses (DOS), comprising the steps of:
separating each bundle of mail seriatim into a single input stream of the individual mail items;
transporting the mail items from the input stream to a staging station;
sorting the mail items at the staging station into a plurality of subsets of mail items re-sequenced as an intermediate step to achieving said final sequence sets;
merging the mail items into a single output stream from the respective subsets of mail items in said final sequenced set; and
collecting portions of the output stream of the mail items consistent with the sequence of the final sequenced set to form batches of mail for orderly delivery to the prioritized delivery addresses (DOS) according to delivery criteria reflected in said final sequenced set.
The sorting of items is performed in a staging tower assembly for storing a plurality of items in vertical stacks above a conveyor in a plurality of juxtaposed towers having a conveying path passing transversely through the towers, each tower comprising: a housing for the tower defining a vertically oriented volume of space, a shelf storage zone in the housing in the space below the conveying path, for storing a plurality of vertically stacked empty shelves separated by a predetermined pitch between the shelves; an item storage space above the conveying path for storing the shelves and items thereon for a stack of items separated by a selected pitch; a transfer zone between the shelf storage zone and the item storage zone for accommodating the conveyor; and an elevator mechanism for moving the shelves one at a time from the shelf storage zone, through the transfer zone, and into the item storage zone; each shelf being capable of picking up articles on the conveyor in the transfer zone and lifting the articles into the item storage zone.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.